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A landmark study by scientists at the University of Oxford, has unveiled crucial insights into the way that COVID-19 vaccines mitigate severe illness in those who have been vaccinated.

3D illustration of a male body fighting and beating red Covid virus

Despite the global success of COVID-19 vaccination campaigns, concerns remain around the continued spread of this disease including in vaccinated individuals. For this reason, researchers at the Oxford Vaccine Group conducted an extensive investigation into the human immune response to COVID-19, in both vaccinated and unvaccinated individuals.

Employing contemporary 'big-data' analyses, scientists can find novel associations between fundamental biological entities and indicators of the severity of a disease — to build patterns of health and disease. Results of this study categorically show a reduction in indicators of disease severity in those who had received the vaccine, demonstrating that the harmful inflammatory reaction to COVID-19 is less severe in those who have been vaccinated, when compared with those who haven’t.

Professor Daniel O'Connor, Head of Bioinformatics at the Oxford Vaccine Group (OVG), led the study. He said: 'These results confirm the efficacy of vaccination and its pivotal role in reducing the harmful consequences associated with COVID-19. The results of our research highlight the ChAdOx1 nCoV-19 vaccine's ability to modulate harmful responses to the SARS-CoV-2 virus, and therefore to reduce the severity of illness. The implications of these findings are far-reaching, offering evidence that is fundamental to future vaccine development and pandemic mitigation strategies. It also provides valuable guidance for policymakers and public health experts.'

Read the full story on the University of Oxford website.

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